Weed Control J 2022; 21: e202200763

Research Article

Auxinic herbicides and tembotrione sprayed on seed-propagated elephant grass

DOI: 10.7824/wcj.2022;21:00763

Abstract

Background

Elephant grass plants propagated by seeds are more likely to have injuries to herbicides, in their initial cultivation phase, when compared to those from cuttings. There are selective herbicides for elephant grass developed from seeds.

Objective

This work evaluated the tolerance of elephant grass implanted by seeds to auxinic herbicides and tembotrione.

Methods

Two experiments were conducted in the municipalities of Valença, Rio de Janeiro State, Brazil, and Coronel Pacheco, Minas Gerais State, Brazil. The experimental design was in randomized complete blocks, with four replications. The experimental treatments were: Auxinic herbicides {fluroxypyr + picloram [160 + 160 g a.e. ha ^-1 ]; fluroxypyr + aminopyralid [160 + 80 g a.e. ha ^-1 ]; fluroxypyr + triclopyr [160 + 480 g a.e. ha ^-1 ]; 2,4-D amine (1,340 g a.e. ha ^-1 ); 2,4-D amine + picloram [720 + 45 g a.e. ha ^-1 ]}, and tembotrione (84 g a.i. ha ^-1 without mineral oil), in addition to the control without herbicides.

Results

Tembotrione was the most phytotoxic treatment to elephant grass propagated by seed, causing leaf bleaching and, consequently, reducing forage dry matter yield. The treatments with fluroxypyr + picloram, fluroxypyr + aminopyralid, fluroxypyr + triclopyr, 2,4-D and 2,4-D + picloram did not cause symptoms of phytotoxicity capable of providing a reduction in forage productivity, being potential herbicides for spraying in seed-propagated elephant grass fields.

Conclusions

the herbicides: fluroxypyr + picloram, fluroxypyr + aminopyralid, fluroxypyr + triclopyr, 2,4-D and 2,4-D + picloram can be sprayed in the elephant grass developed from seeds.